Effects of quantization in phase-shifting digital holography software

Dynamic digital holography for recording and reconstruction. Mirror with pzt half mirror phase shift half mirror figure 53. Digital holography applications in ophthalmology, biometry. The influence of bitdepth limitation in quantization has. To this end, we derive a method for retrieving the amplitude and phase of the object wave through a.

We have recently studied the effects of reduction of bit depths in. The technological developments of digital sensors and optical elements have made dh the primary. Jay krishna ananad, indian institute of space science and technology india. Random noise is also added to the multiplexed hologram.

For example, psfs quantized at discrete levels around the wrp can be. We propose integrated phase shifting digital holography using statistical approach. A new method for threedimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phaseshifting interferometry and then fresnel transformed by a digital computer. Comparison of digital holography and transport of intensity for. The phase shifting or phase stepped digital holography process entails capturing multiple interferograms that each indicate the optical phase relationships between light returned from all points on the illuminated object and a controlled reference beam of light. Effects of quantization in phaseshifting digital holography. We vary bit depths of phaseshifted holograms in both numerical simulation and experiments and then derived the complex. Chapter 5 phaseshifting digital holography principles and. Quantization has very good effect and reductions to as few as 3 bits in each. Development of an optical heterogeneity evaluation system. However, no simultaneous reconstruction of absorption and phaseshifting distributions from a single terahertz inline hologram has yet been reported. On fresnelets, interference fringes, and digital holography. In particular, holograms generated by the phaseshifting digital holography method are tested, and the compression is performed by scalar uniform and adaptive quantization and by vector.

In order to achieve highprecision nondestructive evaluation of optical heterogeneity, we develop a versatile evaluation system using the parallel phase shift digital holography, which enables measurements of the optical path differences. It has been known that the accuracy of phase shifting digital holography is limited mainly by the phase tolerance of reference. We discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital holography. Strategies for reducing speckle noise in digital holography. Demonstration of compression ratio of over 4000 times for. Uncertaintymanaged phaseshifting digital holography. Digital holography dh has emerged as one of the most effective coherent. Effects of quantization in phaseshifting digital holography osa. With phaseshifting holography, it is possible to obtain the two quadratures of the field even though the conjugate image alias and the true image overlap, because aliases can be removed by taking image differences. Signal processing challenges for digital holographic video. Motion compensation and noise tolerance in phaseshifting. It is free from tedious photographic processing and delivers threedimensional distributions of both amplitude and phase quantitatively.

Superresolution imaging method using phaseshifting digital lensless fourier holography luis granero 1, vicente mico 2, zeev zalevsky 3, and javier garcia 2 1aido technological institute of optics, color and imaging, c nicolas copernico 7, 46980, paterna, spain. Digital holography dh has emerged as one of the most effective coherent imaging technologies. Introduction digital holography dh is a measurementtechniquebased on an interferometricprinciple, whichenables the recovery of both the amplitude and phase of a wavefront. The required intensity quantization level is helpful for selecting a digital image sensor. The following challenges in the design of holographic display impact signal processing requirements.

Digital holography, phase shifting interferometry, oneshot hologram 1. Gabor in line digital holography in imaging concealed objects 12. Digital holography refers to the acquisition and processing of holograms with a digital sensor array, typically a ccd camera or a similar device. Image rendering, or reconstruction of object data is performed numerically from digitized interferograms. Request pdf phaseshifting digital holographic data compression modern holography for 3d.

The results based on the digital in line holography show that the two fourstep phase shifting algorithms possess different sensitivity to the phase shifting errors, and the preferable one. Terahertz inline digital holography of dragonfly hindwing. Computer simulation and experimental results have been performed to verify the effectiveness and feasibility of our proposed method. Superresolution imaging method using phase shifting. Openaccess holographic data are selected and characterized as references for the experimental analysis. In one of our previous works the preliminaries of an all digital holographic approach to 3dtv were given. In order to reconstruct the threedimensional features of objects is broadly used the phase shifting technique in digital holography 31, the images resulting from this process withdraw the zero order term and the conjugated image of the object, that are usually seen in dh. The reconstructed wavefield contains phase and intensity distributions, which means it is full 3d, exhibiting such effects as depth and parallax. Furthermore, the design of phaseshift digital holography psdh gives.

This technique enables the measurement of both amplitude and phase, useful for quantify. In addition, the phaseshifting errors may cumulate or not according to different phaseshifting techniques, and both cases are considered in this paper. We propose integrated phaseshifting digital holography using statistical approach. Strategies for reducing speckle noise in digital holography ncbi. To perform phase shifting digital holography psdh, several holograms have to be recorded, each with the phase of the reference wave shifted to different states. A phase shifting interferometer records the phase and amplitude information generated by a threedimensional object at a plane located in the fresnel diffraction region with an intensityrecording device.

The purpose of this third edition is to bring together in a single book descriptions of all tests carried out in the optical shop that are applicable to optical components and systems. Interferometry is the technique of superimposing interfering two or more waves, to detect differences between them. This project was supported by the research fund for the doctoral program of. Therefore, the concept of digital holography is a promising approach to 3dtv. Suppression of the zeroorder and twin images by phaseshifting digital holography allows efficient use of the pixel array 24. In one of our previous works the preliminaries of an alldigitalholographic approach to 3dtv were given. Oneshot phaseshifting digital holography based on the. The authors present a parallel phaseshifting digital holography as a digital imaging technique for recording and reconstruction of threedimensional object. A new method for threedimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phase shifting interferometry and then fresnel transformed by a digital computer. In twostep quadrature phaseshifting holography, two phaseshifting onaxis holograms with a zero phase shift and a p2 phase shift are achieved, as follows. We next propose a versatile pcmpoh codec with progressive quantization that can adapt to slmdynamicrange and available. A lowpower headmounted phaseonly holographic display by. The method can reconstruct an arbitrary cross section of a threedimensional object with higher image quality and a wider viewing angle than from conventional digital holography. Highresolution quantitative phase contrast microscopy by digital holography christopher j.

There is currently a great deal of research being done in optical engineering. Abstract we discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital holography. A method and system for encrypting multidimensional information utilizing digital holography is presented. As a side effect, the zeroorder term and the twin image can be eliminated in the reconstructed image. We vary bit depths of phaseshifted holograms in both numerical. This book is intended for the specialist as well as the nonspecialist engaged in optical shop testing.

The best known example is phaseshifting digital holography, where generally at least 3 exposures are needed to unambiguously retrieve the complex amplitudes cf. Optics and photonics for advanced dimensional metrology. In the field of coherent metrology, the effects of quantization in phaseshifting interferome try 14,15, fringe analysis 1, and phaseshifting digital holography psdh 16, 17 have been. Narayanamurthy, indian institute of space science and technology india. In ref 21, the authors studied the effect of quantization in phase shifting digital holography and it was shown that the use of 4 bits for hologram quantization is adequate for visual. While there are several methods for zeroorder and twin image elimination or suppression, phaseshifting holography psh 1, 2, 3 has been the most widely used technique for this task. Quantization noise and its reduction in lensless fourier. Other readers will always be interested in your opinion of the books youve read. Encryption is performed by utilizing the fresnel diffraction pattern of a random.

A phaseshifting interferometer records the phase and amplitude information generated by a threedimensional object at a plane located in the fresnel diffraction region with an intensityrecording device. The technique is implemented by inserting a phaseshifting array device consisting of array of 2. Suppression of the zeroorder and twin images by phase shifting digital holography allows efficient use of the pixel array 24. Wave front reconstruction by means of phaseshifting. The optical phase of the reference beam is shifted from one sampled interferogram. Lightinflight recording by parallel phaseshifting digital. Nov 29, 20 we compare the influence of intensity quantization in ppsdh with that in the conventional phase shifting method. Superresolution imaging method using phase shifting digital. In the paper, they have presented a new application of digital holography for phase contrast imaging. In the integrated phaseshifting scheme, the phase shifts are generated by a reference mirror moving with a uniform velocity, and sequential phaseshifted holograms are captured. The compression method is based on delta modulation and row decimation. In digital holography, one of the most important tasks is to eliminate the undesired zeroorder and twin image to obtain a high quality reconstruction. Setup for microscopy using phaseshifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5.

The image quality and resolution limits of phaseshifting. A significant constraint of digital holography is the pixel count and resolution of the imaging devices. We next propose a versatile pcmpoh codec with progressive quantization that can adapt to slmdynamicrange and available bitrate, and features perpixel ratedistortion control to achieve. Phd and mphil thesis classes mural maynooth university. Techniques of digital holography are improved in order to obtain high. Dec 14, 2010 a method of a digital holography based on the use of a selfimaging of the phase element is presented and assessed in terms of image quality and resolution. Phaseshifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. Effects of quantization in phaseshifting digital holography, appl.

Introduction in digital holography, holograms are recorded using an image sensor such as ccd cameras, and reconstruction of images of the object is performed by a computer. Signal processing challenges for digital holographic video display. Digital holographybased security schemes book chapter. The experimental results of digital hologram acquisition and reconstructions are given for a standard usaf test pattern. In this case the drawback is that precisely controlled subwavelength translations of the sample or of a reference mirror are required. More exposures can be taken to improve noise robustness. The results based on the digital inline holography show that the two fourstep phaseshifting algorithms possess different sensitivity to the phaseshifting errors, and the preferable one.

Investigation on temporal phase shifting in digital shearography during transient process paper 152249 authors. Phase shifting digital holography has been used for the study of vibrating objects. However, no simultaneous reconstruction of absorption and phase shifting distributions from a single terahertz in line hologram has yet been reported. Javidi, a companding approach for nonuniform quantization of digital holograms of threedimensional objects, optics express 1412, 512954 2006. Wave front reconstruction by means of phaseshifting digital. For hologram recording a conventional holographic setup can be used, as long as a phase shifting element is included in the optical path of the reference beam see fig. Yamaguchi, threedimensional microscopy and measurement by phaseshifting digital holography, selected papers from fifth international conference on correlation optics, o. Encoding and decoding processes are low in complexity, enabling realtime operation. Parallel phaseshifting digital holography using lcosslm. Digital holography for quantitative phasecontrast imaging.

Whether youve loved the book or not, if you give your honest and detailed thoughts then people will find new books that are right for them. Effect of phaseshifting error on deformation evaluation. Gabor inline digital holography in imaging concealed objects 12. Small amount of storage memory is needed in the encoding and decoding processes. Phase shifting digital holography allows elimina tion of zeroorder and twinimage components even in onaxis arrangemen t 68. A new estimation method for twosteponly quadrature phase. Fast method of recovering referencewave intensity in two. Single shot digital holography using iterative reconstruction.

Phase shifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. Yamaguchi, effects of quantization in phaseshifting digital holography, applied optics 4416, 12161225 2005. Principles and techniques of digital holographic microscopy. We propose and demonstrate light in flight recording by parallel phase shifting digital holography to obtain a motion picture of ultrashort light pulse propagation free from unwanted images, which are a zerothorder diffraction image and a conjugate image, by phase shifting interferometry with a singleshot exposure. Digital holography, image reconstruction technique, interferometric imaging, phase measurement. Digital holography offers a means of measuring optical phase data and typically delivers threedimensional surface or optical thickness images. Introduction digital holography has many versatile applications, including microscopy 1, phase contrast 2, 3d displays 3, tomography 4, and terahertz imaging 5. Freeviewpoint images captured using phaseshifting synthetic aperture digital holography tatsuya nakatsuji and kyoji matsushima department of electrical and electronic engineering, kansai university, yamatecho 3335, suita, osaka 5648680, japan corresponding author. Threechannel color digital holography has been demonstrated 10. Quantization noise and its reduction in lensless fourier digital. We identify challenges in hardware and software and collect a set of. We have recently studied the effects of reduction of bitdepths in. Phaseshifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. The technique uses a ccd camera for recording of a digital fresnel offaxis hologram and a numerical method for hologram reconstruction.

The method simultaneously provides an amplitudecontrast image and a quantitative phase contrast image. Phaseshifting digital holography allows elimina tion of zeroorder and twinimage components even in onaxis arrangemen t 68. Highresolution quantitative phasecontrast microscopy by. May 15, 2006 we present a technique for phase shifting digital in line holography which compensates for lateral object motion. This method has been coupled with microscopy 1 for applications such. Phaseshifting digital holography which is available simply with single holograms without any special phaseshifting device is proposed.

Phaseshifting digital holography is widely used to determine the phase as well as the amplitude of the objects wave 1, 2. Digital gabor holography, without separate reference. Digital holography represents a novel media which promises to revolutionize the way the users interacts with content. Comparative study of scalar and vector quantization on. The nondestructive, noncontact, threedimensional evaluation of optical glass has been important to the manufacturing of highprecision optical components. Freeviewpoint images captured using phaseshifting synthetic. The best known example is phase shifting digital holography, where generally at least 3 exposures are needed to unambiguously retrieve the complex amplitudes cf. In the integrated phase shifting scheme, the phase shifts are generated by a reference mirror moving with a uniform velocity, and sequential phaseshifted holograms are captured.

Effects of 2d phase unwrapping and flat quantization on compression performance are also reported. You need an ereader or compatible software to experience the benefits of the. Amongst the various dh methods, digital phaseshifting interferometry stands out. Phase shifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. Phaseshifting digital holographic data compression request pdf. Offaxis and in line holographic schemes have their advantages and disadvantages 14. We vary bit depths of phaseshifted holograms in both numerical simulation and experiments and then derived the complex amplitude, which is subjected to fresnel transformation for the image reconstruction. In digital holography holograms are recorded by a ccd and image reconstruction is performed by a computer. Traditionally, interferograms were measured by locating the center of a fringe and then tracing along the fringe. Optical scanning holography can generate holographic images of fluorescence 9. Effect of intensity quantization level in parallel phase. Also see 20 for a survey on quantization in holography. The timeaveraged complex amplitude of fresnel diffracted field due to a vibrating object was obtained by using.

From this, digital holography has following attractive features. Lowcomplexity compression of holograms based on delta modulation. Thelowest quantizationonecanachieve directly is 1bit per pixel, the binary hologram. Strategies for reducing speckle noise in digital holography nature. In phaseshifting digital holography, darakis et al. Image reconstruction only by phase data in phaseshifting. Setup for microscopy using phase shifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. The best known example is phaseshifting digital holography 64, where. In addition, the phase shifting errors may cumulate or not according to different phase shifting techniques, and both cases are considered in this paper. A method for compressing optical scanning hologram by 64 times has been developed. Freeviewpoint images captured using phase shifting synthetic aperture digital holography tatsuya nakatsuji and kyoji matsushima department of electrical and electronic engineering, kansai university, yamatecho 3335, suita, osaka 5648680, japan corresponding author. Interferometry is applied in a wide variety of fields, including astronomy, fiber optics, optical metrology, oceanography, seismology, quantum mechanics and plasma physics. The decoded hologram is real and can be displayed on a spatial light modulator. It has been known that the accuracy of phaseshifting digital holography is limited mainly by the phase tolerance of reference.

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